[ifinnegan]

Biggest mistake in history was allowing any other country to develop their own atomic weapons.

[nascarnation]

Given the widespread penetration of Soviet agents in the US (remember we were allies in WW2) it was impossible to maintain the secrecy needed.

[Verginius Rufus]

Once we used the bomb and other countries knew it was possible to make it, I don't think there was any way we could have prevented proliferation.

C-SPAN 3 has run Winston Churchill's "Iron Curtain" speech from March 1946 a couple of times lately. In the course of the speech he comments on how fortunate it was that it was the US which first acquired the bomb. Of course at that time we still had a monopoly.